复杂环境条件下的洞内管井降水技术研究

Research of the Tunnel and Dewatering Technology under Complicated Environment Conditions

城市中心密集建筑群使得地铁需长距离穿越既有建(构)筑物,导致地面管井施工作业条件越来越难,降水沉降控制要求也越来越严。从轨道交通工程建设出发,当受施工场地限制时,提出在导洞内施工管井,并对降水导洞的设计、成井机械及施工工法进行了论述。针对施工降水引起的附加沉降,采用地下水三维渗流与地面沉降耦合模型计算软件——Processing Modflow,建立地下水流场与地面沉降的耦合模型,根据现场监测数据,运用参数修正后的模型,设计不同的抽降方案,分时段进行沉降预测,及时分析施工降水对周围环境的影响程度,可指导类似工程施工,具有重要的工程实际意义。

City center metro dense buildings need to make a long distance through the existing building （structure）, re- sulting in ground tube well construction and more difficult operating conditions, precipitation, sedimentation control require- ments have become more stringent. In this paper, starting from the rail transit construction, when restricted by the construc- tion site, construction of tube wells proposed in the guide hole, and precipitation guide hole design, as well machinery and con- struction method are discussed. For additional settlement construction precipitation caused by the use of three-dimensional groundwater flow model coupled with land subsidence calculation software--Processing Modflow, establish coupling model of groundwater flow field and land subsidence, according to the on-site monitoring data, the model parameters using the modified, different designs pumping down the program, scheduled settlement prediction conduct timely analysis of the impact of construc- tion on the surrounding environment of precipitation, and can guide a similar construction, the project has an important practi- cal significance.